Bay is considered as any shade of brown between bay/brown, and chestnut. A bay's limbs, mane and tail are always black however.
Brown is considered as a mixture of black and brown in the coat. Black limbs, mane and tail.
Black is considered as a uniform black colour (except possible white markings on its head and lower legs).Coat, limbs, mane and tail are predominantly black.
Chestnut is considered as to vary from light, washy yellow to dark liver orange, and in between are red, gold and liver shades.
Grey is considered as a mixture of black and white hair.
Roan is considered as a mixture of red and white, or brown and white. Limbs, mane, and tail many be black, roan, or chestnut.